var createError = require("http-errors");
var express = require("express");
var path = require("path");
var cookieParser = require("cookie-parser");
var logger = require("morgan");
const jwtAuth = require("./utils/auth");

//引入mongoose
var mongoose = require("mongoose");
// 链接到数据库
const dbUrl = "/mongodb://localhost:27017/exam";
// 链接命令
mongoose.connect(dbUrl, { useNewUrlParser: true, useUnifiedTopology: true });
// 链接监听
mongoose.connection.on("connected", () =>
  console.log(dbUrl + "数据库链接成功")
);

const studentsRouter = require("./routes/students");
const imagesRouter = require("./routes/images");
const testsRouter = require("./routes/tests");
const exercisesRouter = require("./routes/exercises");
const testedRouter = require("./routes/tested");
const errorsRouter = require("./routes/errors");
const collectionsRouter = require("./routes/collections");

var app = express();

// 设置 CORS 允许跨域
var allowCrossDomain = function (req, res, next) {
  // 设置允许哪一个源（域）可以进行跨域访问，* 表示所有源
  res.header("Access-Control-Allow-Origin", "*");
  // 设置允许跨域访问的请求头
  res.header(
    "Access-Control-Allow-Headers",
    "X-Requested-With,Origin,Content-Type,Accept,Authorization"
  );
  // 设置允许跨域访问的请求类型
  res.header("Access-Control-Allow-Methods", "PUT,POST,GET,DELETE");
  // 设置允许 cookie 发送到服务器
  res.header("Access-Control-Allow-Credentials", "true");
  next();
};
app.use(allowCrossDomain); // 使用该中间件

// view engine setup
app.set("views", path.join(__dirname, "views"));
app.set("view engine", "jade");

app.use(logger("dev"));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, "public")));

// 让 token 验证规则生效
// 一级接口之前
app.use(jwtAuth);
app.use("/students", studentsRouter);
app.use("/images", imagesRouter);
app.use("/tests", testsRouter);
app.use("/exercises", exercisesRouter);
app.use("/tested", testedRouter);
app.use("/errors", errorsRouter);
app.use("/collections", collectionsRouter);

// catch 404 and forward to error handler
app.use(function (req, res, next) {
  next(createError(404));
});

// error handler
app.use(function (err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get("env") === "development" ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render("error");
});

// module.exports = app;
app.listen(3000, () => console.log("3000 端口已经开启"));
